Here's why there's no single "best" number:
* Incorrect answers are penalized: The GRE Psychology Subject Test has a penalty for incorrect answers. This means randomly guessing is generally a bad strategy.
* Your knowledge varies: You'll be more confident on some questions than others. Leaving blanks on questions you genuinely don't know anything about is better than guessing wildly.
* Confidence is key: Focus on identifying questions where you can eliminate at least one or two options with confidence. Guessing from a reduced pool of options is far more effective than random guessing.
Instead of focusing on a number of blanks, focus on this:
* Answer only the questions you're confident about: If you can confidently eliminate choices, that's a good reason to guess. If you're completely unsure, leaving it blank is usually a better strategy.
* Manage your time effectively: Don't spend too much time on any single question. If you're stuck, move on and come back if you have time at the end.
* Practice tests are crucial: Take several practice tests under timed conditions to gauge your performance and determine your guessing accuracy. Analyze your mistakes to understand your strengths and weaknesses.
In short, the best approach isn't about leaving a specific number of questions blank, but rather about strategically selecting which questions to answer and which to leave blank based on your knowledge and confidence level. Focus on maximizing your score through accuracy and efficient time management.